The present invention relates generally to a rollover protective structure for use with orchard tractors and, more particularly, to a telescopic or collapsible rollover protective structure that is movable between raised and lowered positions.
Fixed rollover protective structures, commonly referred to as ROPS, are provided with a structural member extending above the operator of a vehicle, such as a tractor, so that the operator can be retained, when used in cooperation with a restraint system such as a seat belt, within a protective envelope in the event the vehicle rolls over. Accordingly, fixed ROPS devices are typically the tallest structure on a tractor. In certain instances, such as when the tractor is operating in an orchard having low hanging fruit bearing tree limbs, it is desirable to remove the fixed ROPS out of interference with such obstacles. To facilitate operation of tractors in orchards, collapsible ROPS devices have been developed, such as shown in U.S. Pat. No. 4,949,991.
A telescopic ROPS has been marketed by John Deere and Company as a telescoping "ROLL-GARD" mounted on their Model 2855N Orchard and Vineyard tractors. This telescoping "ROLL-GARD" structure collapses from an up position to a down position in which the cross member is positioned generally lower than the operator. However, when the tractor is no longer being utilized in an orchard environment, the ROPS can be returned to the up position to provide the proper rollover protection. This telescoping ROPS utilizes a fastener to retain the ROPS in the up and down positions, but, otherwise, this fastener becomes a loose piece of hardware when the ROPS is in the down position. Furthermore, this particular telescoping ROPS requires the operator to bear the weight of the movable protective member when moving the ROPS to either the up or the down positions.